Field of the Invention
The present invention relates generally to the fields of biophysics, bioelectromechanics, bioengineering, tissue engineering and cellular regeneration. Specifically, the present invention relates to an alternating ionic magnetic resonance (AIMR) multiple-chambered culture apparatus for potentiating or controlling the growth of biological cells and tissues, such as mammalian tissue.
Description of the Related Art
Prior to the development of bioreactors, cell culture was limited to systems subjected to the forces of gravity, with most laboratory cultures producing flat two-dimensional (2D), one cell thick specimens unlike the natural three-dimensional (3D) environment of a complex, multi-cellular organism. Most laboratory experiments therefore had inherent limitations and a strictly one-dimensional view of understanding how cells grew and interacted with one another in their natural environment.
With the development of bioreactors, most of these devices were “stirred tank” bioreactors that used a vertical aspect configuration with a stirring device at the bottom of the growth chamber to mix the cells and fluid medium suspension. Horizontally rotating bioreactors offered a way to minimize or neutralize the sedimentation and shear effects caused by gravity by using the “clinostat principal” in which a fluid medium was rotated about a horizontal axis thus minimizing the wall effects and impeller impacts of internal stirring devices and lowering the overall Reynolds and Coriolis force effect on cells.
Cells grown in rotating bioreactors were suspended in a fluid medium and were continually rotated away from the surfaces of the vessel which enabled cells to adhere to one another and to grow. This type of suspended cell culture resembled growth mechanics in a naturally occurring tissue and in a multidimensional form and thereby promoted more realistic, three-dimensional cell-to-cell contact signaling. These 3D cells were induced to regulate and to produce cellular components as if grown within a complex organism and to produce complex matrices comprising extracellular matrix molecules, proteins, fibers, and other cellular components. These aforementioned processes lead to autoregulation and the ability to self-order in the human mammalian physiology. Inside a complex organism, these components often informed a cell of the neighboring environment and triggered a specific set of responses to that external environment. The cell grew or it became static, which in turn, determined how the cell responded with the production of secondary regulators.
A typical rotating bioreactor had an outer tubular enclosure with transverse end walls and end caps in the end walls. The outer tubular enclosure was supported on input and output shaft members and rotationally driven by an independent drive mechanism. Coaxially disposed within the outer tubular enclosure was a central tubular filter member that was rotationally supported on the input shaft and coupled to the output shaft. The annular space between the inner and outer tubular members defined a cell culture chamber.
Two blade members were positioned about the horizontal axis and extended lengthwise along the cell culture chamber. The blade members had radial arms at one end that were rotationally supported on the output shaft and radial arms at the other end that were coupled to the input shaft. The input shaft was rotationally driven by an independent drive means that normally drove the inner and outer tubular members and the blade members at the same angular rate and direction so that no relative motion occurred between these members. Thus, clinostat motion could be achieved for the particles in the fluid within the cell culture chamber.
Existing bioreactors, however, are overly complicated systems and costly to operate with respect to expenditure of preparation time, upkeep, disposal of non-reusable components. For example, in existing bioreactors the cell samples and any other required initial ingredients must be assembled into the culture system in preparation for an experiment. At the end of the experiment, it is necessary to disassemble significant portions of the culture system in order to extract the cells and/or tissue culture that grew during the experiment. Moreover, because the culture system mechanisms include rotating fluid couplings, leaks may develop over time in the seals of these couplings. Finally, the motors that provide the rotation in existing bioreactors are integral to the system, contributing to the complexity of the system and making it difficult to maintain and operate the system. Accordingly, what is needed is a culture system and method that mitigates or overcomes some or all of the shortcomings of existing bioreactors.
U.S. Pat. Nos. 6,485,963 and 6,673,597 disclose the use of a time-varying electromagnetic force (TVEMF) in a manner that stimulates the proliferation of cells grown in culture. In U.S. Pat. No. 7,179,217, Goodwin et al. disclose the use of a TVEMF sleeve for treatment of an animal limb. Commercial utilization of this technology has provided two approaches to culture system design. The first approach is the use of baffles or plates within the culture system with a time-varying electromagnetic current applied across the plates to induce a time-varying electromagnetic force within the culture chamber. The second approach is to use a coil wrapped around the rotating culture system chamber and affixed thereto with a time-varying electromagnetic current applied to the coil to create a time-varying electromagnetic force within the culture chamber.
There are several limitations with existing culture systems designs that utilize TVEMF in the context of a rotating culture system chamber. First, the existing TVEMF culture systems have the electromagnetic device permanently affixed to the culture chamber unit, which does not allow for the use of disposable modules nor does it accommodate the self-feeding capability of the current invention. Instead, existing systems require periodic and frequent manual exchange of growth media during the culture cycle. Additionally, since the goal of proliferation of cell cultures is in many instances the utilization of the cells and tissues for reintroduction into the human body for tissue regeneration or treatment of human maladies, the culture system chamber must meet the rigid standards of the Food and Drug Administration (FDA). If the EMF inducing device is incorporated into the culture chamber, it significantly complicates the manufacture and sterilization process, and would require routine disposal of the EMF inducing device along with the used culture system chamber. This would significantly add to the cost of the equipment and culturing process for FDA approved purposes.
Another limitation of existing culture systems is that they utilize TVEMF, which does not effectuate the same stimulatory or physiological effect on cultured cells as compared with alternating ionic magnetic resonance. TVEMF fails to stimulate specific ionic species and membrane channel systems that play a major role in the regulation of proliferation, differentiation, tissue repair, and related cellular mechanisms that are inherent to growth, development and maintenance of a mammalian organism. A further limitation is that existing culture systems rely on a batch fed or media perfusion systems to transfer media into and out of the growth chamber. Each of these methodologies fails to provide physiological and homeostatic parameters similar to those of a naturally occurring physiological system.
Thus, there is a recognized need in the art for culture systems that utilize an alternating ionic magnetic resonance field during the three-dimensional culture of cells, including tissues and/or organoid bodies. Particularly, the prior art is deficient in an alternating ionic magnetic resonance system comprising a culturing apparatus that utilizes pre-sterilized and disposable modules and a removable alternating ionic magnetic resonance chamber. The present invention fulfills this long-standing need and desire in the art.